Video: How Smartphone-Addicted Are You?

Do you check your smartphone enough to qualify as an addict? If so, an app called Menthal wants to put you on a “digital diet.”

Menthal tracks your smartphone use by activity — phone calls, Facebook browsing and the like — and shows you which apps you use most, and for how long. “It’s about shielding and protecting your attention from being overwhelmed,” says Alexander Markowitz, a computer-science professor in Germany who designed the app.

Markowitz says people who use Menthal spend an average three hours a day on their phones, turning them on every seven-and-a-half minutes.

Also on the Digits Show: Is GrabTaxi Better Than Uber and Lyft? Smartphones make calling a cab easier than ever. In the West, the Uber and Lyft apps are popular. In Asia, there’s GrabTaxi—a favorite in Singapore, Malaysia and Thailand.